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<b><i><font face="Arial">Define Drawing Background - DEPRECATED</font></i></b>
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<p><font face="Arial Black"><font size=-1>Purpose</font></font>
<dir>The <b>Define Drawing Background</b> function specifies how the WHIP! data
reading application should render the background behind the geometric primitives
to be drawn.</dir>
<font face="Arial Black"><font size=-1>Syntax</font></font>
<br>&nbsp;
<center><table BORDER CELLPADDING=9 WIDTH="772" BORDERCOLOR="#000000" >
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<td VALIGN=TOP WIDTH="17%" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Opcode
format</font></font></font></td>

<td VALIGN=TOP WIDTH="16%" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Opcode</font></font></font></td>

<td VALIGN=TOP WIDTH="37%" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Operand
Format</font></font></font></td>

<td VALIGN=TOP WIDTH="31%" BGCOLOR="#000080"><font face="Arial"><font color="#FFFFFF"><font size=-2>Comments</font></font></font></td>
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<td VALIGN=TOP WIDTH="17%"><font face="Arial"><font size=-2>Extended ASCII</font></font></td>

<td VALIGN=TOP WIDTH="16%"><font face="Courier New"><font size=-2>(Background</font></font></td>

<td VALIGN=TOP WIDTH="37%"><b><font face="Courier New"><font size=-2>&lt;ws>&lt;I<sub>R</sub>>,&lt;I<sub>G</sub>>,&lt;I<sub>B</sub>>,&lt;I<sub>A</sub>>[&lt;ws>])</font></font></b>
<p><b><font face="Courier New"><font size=-2>&lt;ws>&lt;I<sub>I</sub>>[&lt;ws>])</font></font></b></td>

<td VALIGN=TOP WIDTH="31%"><font face="Arial"><font size=-2>The background
color for the drawing.</font></font>
<p><font face="Arial"><font size=-2>The background color index for the
drawing.</font></font></td>
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<dir><i>R, G, B, A</i> Defines a color by the red, green, blue, and alpha
intensity components
<p><i>I</i> Defines a color by an index into the current color map</dir>
<font face="Arial Black"><font size=-1>Details</font></font>
<dir>Before a WHIP! data reading application starts drawing geometric primitives
to the viewing window, the window should normally be cleared. The Define
Background operation specifies the color to which the viewing window is
cleared before drawing begins.
<p>The legal range for the intensity integers is from 0, indicating zero
intensity, to 255, indicating full intensity. In some cases, it may be
desired to overlay a WHIP! data image on top of an already existing screen image.
Consequently, clearing the background is <i>not</i> desired. A zero intensity
alpha indicates that the background color is totally transparent, and the
window is not cleared. A full intensity alpha (255) indicates that the
background color is completely opaque, and the color fully overwrites (clears)
its background. Alpha values between 0 and 255 indicate that, when the
background is drawn, it is blended to a varying degree with the background
image.</dir>
<font face="Arial Black"><font size=-1>Notes</font></font>
<dir>WHIP! data should contain a maximum of one occurrence of the
background opcode, which by convention should be nested inside a <b><a href="DefDwgInfoBlk.html">Define
Drawing Information Block</a></b> opcode.</dir>
<font face="Arial Black"><font size=-1>Default</font></font>
<dir>By default the drawing background is fully transparent:
<dir><font face="Courier New"><font size=-1>(Background 0,0,0,0)</font></font></dir>
</dir>
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